[Dovecot] Resync dovecot index after manual moving mails in maildir

Hello,

i'm new to dovecot and this list. Dovecot works very well after all! I now have a small problem, maybe there is a solution.

For automatically spam learning i've created a maildir folder called "spam learn". Every hour spamassassin scans this folder and learn from the mails or files at this folder. After this learn i move the files to trash. If at this moment a client is connected via imap to this account, the mua (in my case thunderbird) doesnt update its folder view after reselecting the folder. Is this a mua problem or is this a index "problem" in dovecot (i know, it isnt a real problem or bug). If the second is the truth, is there any possibility to tell dovecot to rescan the maildir?

Thanks in advance.

Bye from Germay Danilo